CN109415080A - With gear rack and for producing the method with gear rack for being used for motor vehicles - Google Patents

Abstract

The present invention relates to a kind of for producing the method with gear rack (2) of the transfer of motor vehicle, it includes at least one toothed portion section (21) with one group of teeth portion (22) and at least one shaft segment (24) including having at least one threaded section of coaxial screw thread (25), the screw thread has reach on the axial direction of longitudinal axis (L), wherein it is provided with the separated section including at least one bacillary band tooth section (61) and an axis section (62), at least one described rod-shaped section and one axis section are aligned on shared longitudinal axis (L) and are connected to each other at joint portion (27).Present invention aims to the production process with gear rack of assembling is more effective.The purpose is realized by following step: providing the axis stock piece (36) with the part length (G) of the multiple for axis section length (ls)；It produces on the axis stock piece (36) of the multiple length of reach in being continuous screw thread (25) on longitudinal direction, to produce threaded semi-finished product (37)；Threaded sections (62) are cut into from threaded semi-finished product (37) by length；Band tooth section (61) is provided；Threaded section (62) is bonded to band tooth section (61).

Description

With gear rack and for producing the method with gear rack for being used for motor vehicles

Technical field

The present invention relates to for producing the method for being used for the rack gear of transfer of motor vehicles, the rack gear includes having At least one toothed portion of teeth portion point and at least one shaft portion at least one threaded portion, at least one described screw thread Part is in the axial direction with the coaxial threaded of reach, wherein provides separated section, the separated area Section includes at least one bacillary band tooth section and an axis section in each case, and the separated section is in shared longitudinal direction It is aligned on axis and is connected to each other at joint portion.

The invention further relates to the rack gear of the transfer for motor vehicles, the rack gear includes at least one with teeth portion At least one threaded shaft portion is divided and had to a toothed portion.

Background technique

In vehicle steering mechanism, the steering order as rotary motion is introduced into steering shaft by steering wheel, with turn The pinion gear that the teeth portion of rack gear into device is engaged is attached to the steering shaft.Rack gear is mounted to energy in transfer It is enough in axial direction, i.e. to be shifted along the direction of the longitudinal axis of the rack gear, exist so that the rotation of pinion gear is converted into rack gear Translational motion on the axis vertical direction of rack gear.The tie-rod for being connected to the knuckle for the wheel to be diverted is secured to rack gear, The translational motion of rack gear is converted into divertical motion at the wheel.

Rack gear is configured with small for engaging on predetermined axial length at least one toothed portion point in toothed portion point The teeth portion of gear.In the case where general rack gear, at least one shaft portion abuts toothed region, institute in the direction of the longitudinal axis State shaft portion as to classify with toothed portion in a manner of be configured in a longitudinal direction shape in the shape of a rod, preferably have cylindricality basic Shape, and there is at least one threaded section.Threaded section forms threaded main shaft, which has along longitudinal direction Direction extends the external screw thread of certain reach.In order to be coupled to the auxiliary force of assisted diversion, it is arranged on threaded section There is mainshaft nut, which can be driven to rotate motor-driven mode around longitudinal axis by auxiliary drive device. Main shaft driving device is formd as a result, by the main shaft driving device, is manually introduced in toothed portion point except through pinion gear Except steering force, the auxiliary force assisted the steering force being manually introduced is also applied on rack gear along the longitudinal direction.Make Main shaft driving device for widely used tactic pattern is configured to ball screw driving device, wherein the fillet of screw is configured to use In the raceway groove of ball, ball is recycled between screw thread and mainshaft nut with low friction.Other than threaded section, axle portion Point can have one or more other funtion parts, such as bearing portions, the bearing portions for example can be configured to It is partially cylindrical in shape, to be mounted rack gear in a manner of longitudinalling translate.For being connected to connecting element, the example of pull rod Such as threaded pin can be on longitudinal direction to be attached to toothed portion point back to mutual free end in each case And shaft portion.

In order to the stress for preferably making material property adapt to generate in operation and in order to optimize for constructing function The production in energy region, it is known in the art that initially construction on band tooth section and has threaded toothed portion point Shaft portion is set as and the axis section separated with tooth section.Initially separated section can lead to for its respective function Cross the processing method of for example continuous selection of material, heat treatment process or part heat tempering and process optimization for example, for example Cold forming or thermoforming, milling, grinding etc. design.With tooth section and axis section then on shared longitudinal axis it is coaxial right Standard, and with tooth section and axis section they at the portion of end side, connection end be axially directed to mutual end each other It is connected at joint portion.Therefore, which is also referred to as the rack gear constructed.The connection of section can be such as in DE 10 2007 By means of connecting element realization or such as in JP 2006 46423A or DE 10 2,013 007 described in 018 919A1 Description described in 072A1 is carried out by species, Species joint method, preferably by welding.Axis section and/or with tooth area Section can optionally be connected with other sections.

In the rack gear of manufacture construction, the section, particularly undergone in each case with tooth section and axis section more A procedure of processing.It is especially relative complex that threaded section is manufactured on axis section.So far, initially from staff-like shape, preferably Ground cylindricality or tubulose axle raw material are cut into each section by length, the part in each case by individually further plus Work.For each separated axis section, the fillet of screw of threaded section is cut in cylindricality raw material by subtracting material manufacturing method In；It may be implemented needed for ball screw by grinding, polishing or accurate machining for surface quality and precision Accurate machining.So far, due to for each individually clamping again of axis section and screw thread cutting and milling drum Processing, thus screw thread cutting and grinding need corresponding complicated and time-consuming production process.

Under the background of an above-mentioned basket, it is an object of the invention to especially be provided with the axis section of threaded section For the more efficiently rack gear of arrangement manufacturing process.Thus provide improved rack gear.

Summary of the invention

The purpose is realized by the method according to claim 1 and rack gear according to claim 12.It is advantageously improved It is obtained from corresponding dependent claims.

In order to solve an above-mentioned basket, the method included the following steps is proposed according to the present invention:

The axis stock piece with part length is provided, the part length is the multiple of axis section length；

In generating continuous screw thread in a longitudinal direction on the multiple length of reach on axis stock piece, so as to Produce threaded semi-finished product；

Threaded section is cut into from threaded semi-finished product by length；

Band tooth section is provided；

Threaded section is bonded to band tooth section.

According to the present invention, the production process for the rack gear of productive structure is optimised, because the screw thread of threaded section exists It is at least partly constructed on axis raw material in upstream process step, and the screw thread of threaded section is in the prior art Construction is on the axis section blank customized according to length.Axis raw material herein can in each case as example in by The axis stock piece of long rod type made of rounded material or heterotypic material or as in the elongated tubular that is preferably made of steel The hollow materials of material forms obtains.The axial length of columnar shaft stock piece is only determined by the production method of raw material, former The production method of material is typically provided in continuous mechanical process on longitudinal direction, such as continuously casting, compacting, rolling, stripping From, drawing etc..Axis stock piece can have any part length in principle as a result, however in practice, for logistics and transport The reason of, axis stock piece is usually determined in advance as the size of several meters, such as 2 meters to 10 meters.

The part length of such axis stock piece is the multiple of axis section length, and axis section length is substantially by axis section Limited along the length measured from joint portion to free end in axis vertical direction, and in practice, axis section length In most cases such as less than one meter and usually can for example between 0.1 meter and 0.5 meter, this depend on transfer Embodiment.

In the prior art, part corresponding with axis section length, threaded portion are cut into from axis raw material by length Screw thread in subsequent production stage for example by screw chasing and grinding generate on the mentioned parts.As already mentioned , due to having higher requirements to ball-screw-transmission screw thread, thus produce high production complexity.

The production of screw thread according to the present invention is assisted according to by corresponding auxiliary force --- such as screw pitch, screw thread wheel It exterior feature, surface quality etc. --- the specification that limits in advance and abides by simultaneously and requires tolerance and carried out on shaft portion raw material.For this purpose, It provides and axis stock piece is continuously machined, preferably in the entire of the axis stock piece according to the method for the present invention Axis raw material are continuously machined in length.It can get the axis section with continuous screw thread in a longitudinal direction as a result, Semi-finished product, the axis section semi-finished product are referred to as threaded semi-finished product.

According to the present invention it is possible to by simply by length cut from threaded semi-finished product come generate had it is threaded Partial axis section.For this purpose, cutting out the component with axial length from threaded semi-finished product, the axial length corresponds to axis area Segment length, axis section length usually correspond roughly to required shaft portion length and again optionally while plus additional machinings Length.For optionally needing to prepare joint surface or in view of to due to used joint method --- for example such as rubbing Wipe welding etc. thermal bonding method in being compressed axially --- caused by shorten and to it is described shortening compensate for, Ke Nengxu Want additional machining length.As a result, according to the present invention, the part length of axis stock piece also correspondingly always shaft portion length or The multiple of reach.

Provide band tooth section in downstream processes step, and with tooth section with according to the present invention by from threaded half The axis section that finished product is cut by length and generated is aligned jointly on shared longitudinal axis.This means that axis section axis is aligned It is offset relative to each other in coaxial or parallel mode.Herein, the mutual opposite engagement with tooth section and axis section Face --- joint surface is located at the portion of end side relative to longitudinal axis --- is bonded to each other subsequently, by means of joint method, In, construct joint portion, wherein the section after engagement has shared longitudinal axis.By means of shape cooperation, force-fitting and/ Or the permanent joint method being fixedly connected of realization that material integrally cooperates is suitable in principle.Ratio can be preferably used Such as welding method, such as friction welding, it ensure that economical production and reliable connection.

The advantageous design embodiment of one according to the method for the present invention is the screw thread on axis stock piece with continuous Axial processing (throughput) method generates.This is herein defined as a kind of efficient continuous machine-tooled method, wherein by conduct Continuous externally threaded thread binding is in the shell surface of axis stock piece in the axial direction.In the entire length of axis stock piece Machining on degree --- multiple that the length may be axis section length --- preferably can continue through machining Stand or with it is multiple machining station production line when carry out in a continuous manner.In this way, it is possible in single work step Obtain the axis section semi-finished product correspondingly extended on the multiple length in axis section length or shaft portion length, wherein save Time-consuming clamping again and alignment.

Screw thread preferably has the ball road of at least one ball screw.The profile of the fillet of screw is herein Such as the track groove of the ball of ball screw is optimized for by Gothic profile, Gothic profile is at every kind In the case of can be realized a ball two limit point on restriction bearing.

It can be improved according to the method for the present invention according to the screw thread that rotation is process.Also referred to as continuous rotation is processed Rotation processing be on cylindricality blank generate screw thread continuation method.Herein, added by high-speed rotating rotation For work ring by the outside of fillet of screw incision shaft portion raw material, high-speed rotating rotation processing ring is disposed relative to longitudinal axis It is eccentric and inclined and there is cutter in inside, wherein raw material passes through correspondence while rotating around longitudinal axis In thread pitch axial advancement and be continuously guided through rotation processing ring.Thus particularly economically produce threaded half at Product.Had the advantages that by means of the screw thread that rotation processing generates following another: may be implemented to be suitable for ball-screw in the best way The geometry and surface smoothness of transmission device, this is conducive to ball screw with the smallest mute operation of abrasion. Screw thread can be processed in one way by rotation, wherein the quality of screw thread has met the requirement in ball screw, makes Further processing can be saved by obtaining.

It is alternative or additionally, other can be used and subtracts material or non-subtract material production method, continuous side is preferably used Method --- for example, milling, broaching tool, rolling etc. --- and optionally using for accurate machining or final mach grinding Etc. screw thread is generated, according to the present invention, the screw thread is continuous in the length of axis raw material.

Band tooth section is provided in the downstream processes step for producing rack gear, and with tooth section and according to this hair The bright axis section generated and cutting from threaded semi-finished product by length is aligned jointly on shared longitudinal axis.Band tooth area The joint surface mutually opposite at the portion of end side herein relative to longitudinal axis of section and axis section is subsequently, by means of engagement side Method is bonded to each other, wherein is configured with joint portion.By means of realize it is permanent be fixedly connected shape cooperation, force-fitting and/or The joint method that material integrally cooperates is suitable in principle.Such as welding method, such as friction welding (FW) can be preferably used It connects, it ensure that economical production and reliable connection.

Advantageously, shaft portion stock piece is provided as heat-formable material part and/or cold forming material part and/or subtracts Material machining materials part.For example, stock piece can be provided as the bar through section rolling made of solid material or mention For for welded pipe or seamless pipe.Shaft portion stock piece can be formed as generating before continuous grinding by means of suitable method Specific shape, surface smoothness or material finish, in addition, shaft portion stock piece can also be accordingly by such as scale Very little rolling, compacting, drawing, calibration, removing increase material machine-tooled method or alternative machine-tooled method to subtract in a manner of material and/or non- Subtract material mode to be formed.

Furthermore, it is contemplated that and it is possible that shaft portion original before continuous grinding and before combining screw thread Material pieces are heat-treated.Raw material can continuously be hardened by heat treatment or partially hardened, for example, so that the raw material Expected stress when operation is adapted in an optimal manner.According to the present invention, have the advantage that herein can be with for continuous grinding Economically accurate machining has the hardened surface of great surface quality and accuracy to size.

Other method and step may include: to provide at least one end side end surface of axis section by cutting by length, To construct joint surface.

Other method and step may include: after cutting by length, at least one end side end surface of axis section It is machined out, to construct joint surface.Material machine-tooled method can be subtracted by means of corresponding for joint method to be used Or plastics machine-tooled method prepares the connection end being arranged for being connected to component with tooth；It is suitable for welding for example, can produce Connect the surface smoothness and/or surface shape of method, or can the communicative engagement face to component with tooth carry out any other tune It is whole.

Band tooth section and axis section are preferably soldered to being soldered to each other by friction welding each other, preferably.? In Friction Stir Welding, to be bonded to mutual section and be aligned and be arranged to around institute on the shared longitudinal axis of the section It states longitudinal axis to rotate relative to each other, and the section each other and is respectively formed herein by the direction of the section Or end face including joint surface and force together each other in a longitudinal direction.The frictional heat generated herein makes joint surface molten Melt, so that establishing the welded connecting of material one.

At least one other function section can be provided and at least one described other function section is bonded to band Tooth section and/or axis section.Other function section can be for example including for being connected to pull rod for toothed portion point or shaft portion Coupling part, or be included in and be plugged on the middle section between tooth section and axis section on axial direction.It can be used Carry out fastening function section with above for the identical joining technique of joining technique described by band tooth section and axis section.With these areas Section is the same, can be before splicing according to being machined out according to the method for the present invention to one or more functions section.

The purpose realizes that the rack gear includes having teeth portion extremely by the rack gear of the transfer for motor vehicles At least one threaded shaft portion is divided and had to a few toothed portion, wherein screw thread extends in entire shaft portion length.

Preferably, the value of the pitch of continuous thread is between 5mm and 4 0mm.It is particularly preferred that the value of pitch 5mm with Between 10mm.Preferably, Design of Screw Thread is the raceway of rolling element such as ball and can have Gothic cross-sectional profiles.

Detailed description of the invention

Favorable embodiment of the invention will be described in more detail by attached drawing below, in the accompanying drawings:

Fig. 1 shows the steering system for motor vehicles；

Fig. 2 shows rack gears produced by the invention；

Fig. 3 is shown in the axis section semi-finished product continuously hardened；

Fig. 4 shows the axis section semi-finished product in continuous grinding；

Fig. 5, which is shown, to be rotated for producing axis section semi-finished product when threaded semi-finished product；

Fig. 6 shows the threaded section cut from the threaded semi-finished product according to Fig. 5 by length；

Fig. 7 shows the toothed portion in continuous grinding and divides semi-finished product；

Fig. 8, which is shown, divides semi-finished product in the toothed portion continuously removed；

Fig. 9 is shown from the band tooth section blank cut with tooth section semi-finished product by length according to Fig. 7 or Fig. 8；

Figure 10 is shown before formation transverse to the schematic diagram of the longitudinal axis of mold in the open state；

Figure 11 shows the mold in Figure 10 in subsequent method step in part closed state；

Figure 12 shows the mold in the Figure 11 being in close state in subsequent method step；

Figure 13 shows the mold in Figure 12 in the state that reopens in subsequent method step after such shaping；

Figure 14 is shown with the view in the width direction of teeth portion (on the direction of teeth portion width) transverse to longitudinal direction The band tooth section according to the completion of Figure 13 is gone out；

Figure 15 shows the band tooth section according to the completion of Figure 13 with the view of (in the height direction) towards teeth portion, described View is transverse to longitudinal direction；

Figure 16 is shown across the cross section X1-X1 according to the mold of Figure 11；

Figure 17 shows the cross section X2-X2 for passing through the mold according to Figure 12；

Figure 18 is shown across the cross section X3-X3 according to the mold of Figure 13；

Figure 19 is shown across the cross section Y3-Y3 according to the mold of Figure 13；

Figure 20 shows the band tooth section in second embodiment, the view with the view on the direction of the width of teeth portion Transverse to longitudinal direction and similar with the view of Figure 19；

Figure 21 shows the cross section C-C of the mold across according to fig. 20；

Figure 22 shows the band tooth section in third embodiment, the view with the visual angle in the direction on the width of teeth portion Transverse to longitudinal direction and similar with the view of Figure 19；

Figure 23 shows the cross section D-D of the mold across according to fig. 22；

Figure 24 shows the band tooth section in continuous hardening；

Figure 25 shows threaded section before being clamped in clamping device and with tooth section；

Figure 26 shows the threaded section being in clamping device before friction welding and with tooth section；

Figure 27 shows the threaded section that friction welding is in later in clamping device and with tooth section；

Figure 28 shows the schematic hardness distribution of friction welding connection according to the present invention；

Figure 29 shows band tooth section with solid；

Figure 30 shows the rack gear of the construction in alternative embodiment；

Figure 31 shows the rack gear with V-arrangement back in another alternative embodiment；

Figure 32 shows the rack gear according to Figure 31 with perspective, cut-away view；

Figure 33 shows the rack gear with V-arrangement profile in alternative embodiment；

Figure 34 shows the cross that the mold of the semi-finished product with insertion is passed through before forging in the mode similar with Figure 16 Section；

Figure 35 shows the cross section of the mold according to Figure 34 after forging；

Figure 36 shows the rack gear produced by the invention in another embodiment with solid；

Figure 37 shows the rack gear according to Figure 36 with the view along the direction of the width of teeth portion, and the view is transverse to longitudinal direction Direction；And

Figure 38 shows the rack gear similar with the rack gear of Figure 37 in alternative embodiment.

Specific embodiment

In various figures, identical component appended drawing reference having the same always, therefore, the identical component is usual It is also only identified or refers to respectively in each case and is primary.

Fig. 1 shows the schematic perspective view of motor vehicles steering mechanism 1, wherein the torque as steering torque can be with It is introduced into steering shaft 101 by driver by steering wheel 102.Steering torque is transferred to by steering shaft 101 and is engaged with rack gear 2 Pinion gear 104 is turned to, rack gear 2 and scheduled steering angle is transferred to by turning for motor vehicles by corresponding pull rod 108 To wheel 110.It turns to pinion gear 104 and rack gear 2 is formed together transfer 105.There is transfer 105 shell (not show herein Out), it in the shell, turns to pinion gear 104 and is mounted to rotate, and be mounted to can be along also referred to as axial for rack gear 2 The longitudinal direction A of direction A vertical shift in the both direction indicated by double-head arrow.

It respectively can also be in the electronic of power assist unit 114 or 116 forms in power assist unit 112, alternatively Power assist unit and/or hydraulic power assist unit can be respectively coupled to steering shaft 1, turn to pinion gear 104 or rack gear 2. Auxiliary torque is introduced into steering shaft 1 by corresponding power assist unit 112,114 or 116, in steering pinion gear 104 and/or Auxiliary force is introduced into rack gear 2, thus assists driver to operate and turns to.Three different power assist units shown in Fig. 1 112,114 and 116 the alternative location for the power assist unit to be arranged is shown.Only one position in shown position Usually occupied by power assist unit.It is driven by means of what corresponding power assist unit 112,114 or 116 applied for supporting The auxiliary torque or auxiliary force of member is being considered by the torque sensor 118 in power assist unit 112 or 114 can be set It is determined in the case where the input torque detected.

Steering shaft 1 has the input shaft 103 for being connected to steering wheel 102 and is connected to the output shaft for turning to pinion gear 104 106。

Output shaft 106 is connected to axis 109, axis 109 by being configured to the hinge joint 107 at universal joint portion or universal joint The jackshaft of steering shaft 101 is formed, and axis 109 is turned by other being connected to mutually isostructural hinge joint 107 To the input shaft 119 of device 105.

The rack gear 2 of transfer 105 is separately shown in Fig. 2.Therefore it can be concluded that, rack gear 2 is configured in the shape of a rod Shape and be on A in the axial direction elongated cylindrical basic shape and have longitudinal axis L.Axial direction A positioning At parallel with longitudinal axis L, rack gear 2 be mounted to can in transfer 105 in axial direction A vertical shift.

Rack gear 2 has toothed portion point 21, and toothed portion point 21 is provided with the teeth portion that A extends along the longitudinal direction on a side 22.About longitudinal axis L with teeth portion diametrically opposite lateral structure be rack gear back 23, rack gear back 23 is hereinafter Referred to as back 23.

Rack gear 2 also has shaft portion 24, and shaft portion 24 has screw thread 25, and shaft portion in the example shown in Figure 2 24 are also referred to as threaded section 24.Screw thread 25, which screws, in transfer 105 is combined with mainshaft nut (not shown), the master Axis nut can be driven by power assist unit 116 to be rotated around longitudinal axis L, as a result, can for supporting the power turned to Rack gear 2 is applied to A along the longitudinal direction.

In order to form the ball screw that wherein mainshaft nut is configured to reciprocation cycle ball nut, screw thread 25 exists It can for example be hardened by the steel to manufacture shaft portion 24 to be directed to and roll ball in terms of thread contour and material property It optimizes.

Toothed portion points 21 and shaft portion 24 have an external freedom end 26, the external freedom end 26 in a longitudinal direction back to Each other and form the end that can connect pull rod 108 of rack gear 2.

Rack gear 2 according to the present invention is the rack gear of construction, wherein the toothed portion with teeth portion 22 divides 21 and has screw thread 25 Shaft portion 24 toothed portion is passed through to mutual end above longitudinal direction in toothed portion points 21 and shaft portion 24 Divide 21 end face and the end face of the shaft portion 24 and for example passes through welding method such as friction welding company at joint portion 27 It is connected to each other, the end face is hereinafter referred to as joint surface 28.

Rack gear 2 shown in Fig. 2 in finished product state when being measured along longitudinal axis L have in each case from Free end 26 is until the length Z that joint portion 27 measures, length Z are made of shaft portion length S and toothed portion point length V.Band Toothed portion 21 and shaft portion 24 can preferably be made of solid material.

By means of the configuration of the rack gear 2 formed by single section, shaft portion and toothed portion point without machined parts Diameter, which is contemplated that into, to be different.It as a result, can also be real in the case where not using hollow (pipe) without machining materials Saving in terms of existing material.

Shaft portion and toothed portion point are advantageously formed by solid material, because initial product is more cost effective, manufactures more Simply and including the post-processing in being hardened in it is related to less risk.

In addition, toothed portion point and shaft portion can be by different materials by means of the configuration of the rack gear formed by single section Material is formed.For example, toothed portion is divided preferably by being formed according to the steel grade SAE1040 or 37CrS4 of DIN EN 10083, and axis Part according to the heat treatable steel C45 of DIN EN 10083 preferably by forming.

For the rack gear 2 of productive structure it may first have to provide prefabricated section, the prefabricated section then passes through its joint surface 28 are bonded together at joint portion 27.How be described below can be executed by processing section according to the present invention, is special It is not the rack gear 2 economically executed through productive structure according to the method for the present invention.

The never machined section material part 3 of the production of section starts to carry out, not machined section material part 3 also by Referred to as it is referred to as example not machined shaft material part without machining materials part 3 or in view of further desired use Or not machined band teeth material part.It can be used as example without machining materials part 3 rolling or squeezing out example made of steel Such as there is the rod-shaped material of circular cross section to provide.Part length G without machining materials part 3 can be any ruler in principle It is very little；In practice, the part length G being provided as when the size of diameter is 20mm to 40mm within the scope of 2m to 10m.Part length G points Be not the length Z of rack gear 2 multiple or shaft portion 24 length S multiple or toothed portion points 21 length V multiple, rack gear The length S or toothed portion of 2 length Z or shaft portion 24 point 21 of length V is between about 0.1m and 0.5m.

When being set with particular/special requirement to material hardness, shaft portion or toothed portion point are produced using hardened steel.According to this The hardening of invention can be such as the progress that schematically shows in Fig. 3.It provides made of hardenable steel without machining materials part 3, for example not machined shaft material part, and be aligned in longitudinal axis L without machining materials part 3.It is described to add without machine Work material pieces 3 are vertically moved along machine direction D in the mode parallel with longitudinal axis L, as indicated by the arrow in Fig. 3.Institute It states and is guided through continuous heating 41 herein without machining materials part 3, for example by the line of induction heating apparatus Coil assembly.Laser heating carries out in continuous heating 41, wherein steel is heated above the austenitizing temperature of steel.Adding Adjoining has continuous cooling device 42 on the D of work direction, and heating is equally moved continuously through the company without machining materials part 3 Continuous cooling device 42.Controlled continuous coo1ing is carried out herein by such as gaseous state coolant liquid and/or liquid coolant, thus steel quilt Hardening, therefore realize continuous hardening.Machined parameters, for example, temperature and heating and cooling time and rate, are made according to Steel grade is predefined with targeted material characteristics are hardened.After carrying out continuous coo1ing in continuous cooling device 42, The section semi-finished product 31 of hardening can be obtained, the section semi-finished product 31 of the hardening can be supplied to other processing steps.Such as Shown in the example of Fig. 3, the section semi-finished product after cure operations preferably have cylindricality core area 311, the cylindricality core Region 311 is not endowed with any hardness relative to the initial material without machining materials part 3 and increases.

The advantages of continuous hardening, is the provision of the axis section semi-finished product 31 of hardening, and the axis section semi-finished product 31 of the hardening are big Cause that there is part length G, the part length G without machining materials part 3 correspondingly to correspond to the multiple or axis of the length Z of rack gear The multiple of the length V of the multiple or toothed portion of partial length S point.Thus, it is possible to carry out more economical compared with prior art Manufacture, wherein in the prior art usually by the length for being cut into a section length ls without machining materials before hardening Degree.

It, can be in a simple manner from the axis section semi-finished product 31 of the hardening with part length G by means of segmenting device 43 The hardening section 32 with section length ls is cut by length.This schematically shows in Fig. 9.Since part length G is hard Change the multiple of the section length ls of section 32, thus can economically generate corresponding a large amount of section 32.The section 32 of hardening can To be connected to other sections or may be used as section blank, section blank can be according to the desired use of the section --- example Such as, as axis section, jointing or other function section --- and be machined in other processing steps.

In order to produce rack gear 2, it may be necessary to provide the section in terms of profile with high dimensional accuracy.As in the prior art As common, the grinding to the section blank for having foreshortened to section length ls is cumbersome and complicated.

It is designed to more economical to produce, proposes and schematically shown according to the method for the present invention in Fig. 4.At this It is provided in text with the not machined shaft material part 3 of part length G, such as one not machined shaft material part and without machine Processing axial wood materials and parts 3 are aligned in longitudinal axis L.The not machined shaft material part 3 along machine direction D with longitudinal axis L parallel mode vertically moves, as indicated by the arrow in Fig. 4.Herein, the not machined shaft material part 3 It is guided while the not machined shaft material part 3 as indicated by curved arrow around longitudinal axis L as rotated Pass through continuous grinding device 44.Pass through continuous grinding on its entire part length G without machining materials part 3 as a result, with size Accurate mode is continuously used to grind into circle, it is described without machining materials part 3 in section semi-finished product 33 with accurate in size Continuous grinding device 44 is left along machine direction D while mode is ground.

The section semi-finished product 33 being ground in a manner of accurate in size have be supplied to continuous grinding it is original without The identical part length G of machining materials part 3.By means of the separation of the section semi-finished product 31 for hardening already shown in Fig. 9 Device 43, circular section 34 is ground in a manner of accurate in size can be in a simple manner from the semi-finished product of the grinding 33 are cut by length.Due to section semi-finished product 33 part length G be the section 34 through being ground section length ls multiple, thus Corresponding a large amount of section 34 can economically be generated.Section 34 may be used as section blank, and section blank can be according to the area Section desired use --- for example, as axis section, jointing or other function section --- and in other processing steps It is machined.

Substitution as not machined section material part 3, it can be envisaged that and it is possible that according to shown in Fig. 4 Continuous hardening is machined out the section semi-finished product 31 of hardening by continuous grinding.Therefore, it generates with accurate in size side The section semi-finished product 33 of ground, with part length G the hardening of formula, can be economically from the section semi-finished product 33 of the hardening Multiple sections 34 are cut by length.

It is illustrated schematically how in fig. 5 and fig. by the way that economically productive structure is band according to the method for the present invention The axis section of threaded sections 35.For this purpose, not machined shaft material part 36 is provided, as described by earlier embodiments , there is part length G corresponding with the multiple of shaft portion length S without mach axial wood materials and parts 36.When 24 structure of shaft portion It makes as the threaded portion timesharing with screw thread 25 continuous in the length of the shaft portion 24, the screw thread in axial direction A is long Degree corresponds to shaft portion length S.

Rotational processing apparatus 45 is shown in FIG. 5, the not machined section material part 3 with part length G is along processing Direction D is inserted into rotational processing apparatus 45.By means of atwirl rotation processing head in not machined section material part 3 In gradually cut the screw thread 25 that in axial direction A is extended continuously on entire part length G, the not machined section material Part 3 is moved along machine direction D and is rotating slowly in rotational processing apparatus herein.Pass through the spiral shell in a continuous manner Line rotation processing, be also called for short continuous rotation processing produce have part identical with not machined section material part 3 it is long Spend the threaded semi-finished product 37 of G.

The threaded section 35 with section length ls can fill in each case by means of segmentation in each case 43 are set to cut from threaded semi-finished product 37 by length.Due to the area that the part length G of threaded semi-finished product 37 is threaded section 35 The multiple of segment length ls, thus can economically generate corresponding a large amount of threaded section 35.Threaded section 35 can connect Tooth section is for example connected to other section sections or is used as section blank, and section blank is expected with according to the section blank It is machined in other procedure of processings on the way.

Fig. 7 illustrates how for example be used to produce toothed portion during continuous grinding by means of continuous grinding device 44 21 not machined section material part 3 is divided to be ground to justify on the entire part length G of the not machined section material part 3 Shape size.Alternatively it is possible to which not machined section material part 3 is existed by means of stripping off device 46 as shown in Figure 8 It is continuously machined to certain size on the entire part length G of the not machined section material part 3, to generate size essence True section semi-finished product 33.By comparing with the diagram of not machined shaft material part 3, without mach band teeth material part 32 are not hardened, so as not to complicate any post forming.Therefore, without mach band teeth material part 32 by means of mill The machining for cutting (Fig. 7) or removing (Fig. 8) is cut directly into required length ls preferably by means of sawing later.

Figure 10 to Figure 13 schematically shows the snapshot of the mold 5 in consecutive steps according to the method for the present invention. View, i.e. direction of observation are herein along the width direction B perpendicular to height direction H transverse to longitudinal axis L (axial axis L It is parallel with longitudinal direction A).Width direction B is limited by the direction of the end cross-sectional SE normal alignment with teeth portion 22.In straight-tooth portion In the case of, width direction B is limited with teeth portion width b transverse to the direction that longitudinal axis L extends by teeth portion 22.Height direction H by Radial direction limits, and the radial direction is vertical from back 23 in a manner of L perpendicularly to the longitudinal axis and perpendicular to width direction B Ground extends through the teeth portion 22 of rack gear 2.

Mold 5 includes toothed die component 51 and back mold component 53, and toothed die component 51 has between teeth portion molding Gap 52, teeth portion moldable gap 52 are formed as the negative impression of teeth portion 22, and back mold component 53 has rear portion moldable gap 54.Mold 5 separate in the separating plane T that B in the width direction is parallel to longitudinal axis L extension.Back moldable gap 54 is configured to back 23 Former and as shown in the figure be configured to the back radius R that such as can be clearly observed in the cross-sectional view of Figure 16 Substantially semi-cylinder.It is likewise contemplated that and it is possible that back has Gothic cross-sectional profiles, that is, there is mutual angulation Two convexly curved parts of degree.Upper holding meanss 55 (at the bottom of diagram) along the longitudinal direction A, be parallel to longitudinal axis Line L setting, so as to adjacent with toothed die component 51 in two sides, and lower holding meanss 56 (at the top of diagram) are arranged to It is adjacent with back mold component 53.Along the longitudinal direction back on the side of mold 52,53 in the side of holding meanss 55,56 It is provided with end stop 57.

In order to implement to provide the cylindrical not machined section material with section length lz according to the method for the present invention Part 3, not machined section material part 3 are hereinafter also called blank 3 for short, according to this method, not machined section material Materials and parts 3 are heated to 750 DEG C to 1250 DEG C of forging temperature, and are inserted into band tooth moldable gap 52 and back moldable gap 53 In, band tooth moldable gap and back moldable gap are separated from each other in open position.Pass through the folder between holding meanss 55 and 56 It holds to carry out the radially fixed of restriction of the longitudinal axis L of blank 3 relative to mold 5.By free end 26 in longitudinal direction A On be parked in blank 3 in end stop 57, blank 3 is axially located as a result, that is, blank 3 is on the direction of longitudinal axis L Positioning.

Back mold component 53 is from shifted against according to the opening state and height direction H of Figure 10, such as by arrow in Figure 10 Indicated by head, until back moldable gap 54 (top of Cong Tuzhong) is supported in the rear lateral portion on blank 3, such as Figure 11 With shown in Figure 16.It can be learnt from the sectional view of Figure 16, cylindricality blank 3 has blank radius r, required according to the present invention It wants, blank radius r is smaller than the radius of rear portion moldable gap 54, i.e. back radius R.Therefore, back moldable gap 54 is initial only It is supported on the excircle in the dorsal area of blank 3 in a linear fashion.Back mold component 53 is now currently located in forging position.

Forging stroke carries out in the next step, wherein toothed die component 51 is along the height side of L perpendicularly to the longitudinal axis It is mobile towards the teeth portion side of blank 3 to H (upward in figure), as indicated by the arrow in Figure 11 and Figure 12.Blank 3 at Shape is carried out by following manner herein: being plastically deformed the material in forging temperature, preferably steel, wherein material flowing And it is filled in the chamber between back mold component 53 and toothed die component 51.Back moldable gap 54 is stamped at base as a result, In the rear lateral portion of part 3, so that it is configured with the back 23 of back radius R, and on the side opposite about longitudinal axis L, Teeth portion 22 is stamped in band flank portion by band tooth moldable gap 51, so that being configured to toothed portion point 21.By this method, blank 3 has been Be formed as band tooth section 61, there is toothed portion point 21 and the transition portion 210 adjacent with toothed portion point 21 with tooth section 61 With 211, wherein toothed portion point 21 has teeth portion 22 and back 23.Teeth portion 22 includes tooth root plane ZFE.210 He of transition portion 211 is undeformed in forging and therefore keep blank radius r identical with blank 3 and longitudinal axis L.Can with for example in band The joint surface 28 of the axis section engagement of 35 form of threaded sections is located at the end side portion at the free end of transition portion 210.

The final position for forging stroke passes through the cross section diagram of the cross section X2-X2 of toothed portion point 21 in Figure 17 Out.Herein as can be seen that the pressure in the height direction H of L perpendicularly to the longitudinal axis arrives greatly so that with tooth mould in forging Has the quilt on width direction B in separating plane T of the material in the toothed portion point 21 between component 51 and back mold component 53 It laterally outwardly squeezes out, is formed simultaneously relative to width B flash 29 outstanding, flash 29 has flash wide relative to longitudinal axis L Spend GB.Flash 29 is spaced apart with flash interval Z with tooth root plane ZFE in height direction H.Flash interval Z is in height direction H The minimum interval between tooth root plane ZFE and the peripheral edge margin of corresponding flash 29 of upper measurement.The week of corresponding flash 29 Edge region is formed by the region being freely formed.In order to especially definitely construct teeth portion 22, the value that flash interval Z has in forming Preferably less than the 20% of back radius R.The value that flash interval Z has particularly preferably is less than the 15% of back radius R.Flash The value that interval Z has is more preferably less than the 5% of back radius R.Since the flash being freely formed is configured to close to tooth root plane ZFE, it is thus achieved that the improvement configuration of the structure of improved flow behavior and teeth portion 22 when forming.

Back radius R in toothed portion point 21 limits back axis Q, and back 23 is with its corresponding semi-cylinder or part cylinder Shape is extended around the rear portion axis with coaxial manner.It is compressed caused by due in forming and associated in width side with compression Flowing on B, when measuring on width direction B, back is endowed back corresponding with twice of back radius R width (2 ×R).The teeth portion 22 opposite with back 23 is endowed teeth portion width b due to forming and on width direction B.Preferably generate with The available teeth portion width b that back width (2 × R) substantially corresponds to, it is wide that available teeth portion width b is also referred to as tooth root Degree.It is realized by back 23 and the optimal radial of teeth portion 22 is supported and is achieved in high bending resistance.

Since according to the method for the present invention, both back width (2 × R) and teeth portion width b can be greater than blank 3 not Machined diameter (2 × r), the not machined diameter (2 × r) correspond to twice of not machined radius.Change as a result, It has been apt to the power being introduced into teeth portion 22 from steering pinion gear 104.Furthermore, it is possible to realize optimization of the back 23 in transfer 105 Installation, the back 23 is broadened relative to blank 3.

After forging stroke, back mold component 53 and toothed die component 51 are again with opposite with forging stroke anti- It is separated to stroke motion, it is as shown in Figure 13 and as indicated by arrow.Mold 5 is again turned on as a result, such as institute in Figure 10 Show.That completes can remove with tooth section 61 from the mold 5 in the position, and new blank 3 can be inserted, in Figure 10 It is shown.

Complete with tooth section 61 in Figure 14 on the width direction B of longitudinal axis L and therefore in tooth The side view parallel with teeth portion 22 illustrates on the direction of portion width b, and complete band tooth section 61 in Figure 15 with teeth portion 21 On plane transverse to longitudinal axis L and therefore opposite with height direction H illustrate.

From Figure 16 to Figure 19, particularly the cross section shown in Figure 19 it can be concluded that, formed the axis of blank 3 and The longitudinal axis L that the axis of transition portion 210 is accordingly formed after forming is consistent with back axis Q, and back axis Q is due to back Portion radius R is surround in coaxial fashion by back 23.It is in Figure 19 it will be clear that this coaxially arranged, wherein without It is related to identical axis L and Q respectively to machine radius r and back radius R.

Second embodiment according to the present invention with tooth section 611 is in Figure 20 with corresponding with the side view of Figure 14 Side view illustrates, and is shown with the section similar fashion with Figure 19 with the section C-C for passing through transition portion 210.With band tooth area Edge is radially inclined towards the direction of teeth portion 21 in parallel on the contrary, back axis Q is herein relative to longitudinal axis L for section 61 Shifting, the interval c1 for specifically offseting by referred to as offset.Offset c1 correspond in the example shown radius and between difference R-r and therefore it is greater than and zero and is properly termed as positive offset amount.When viewed in cross section, back 23 terminates in radial directions In the circumference minimum point of transition portion 210.Therefore, teeth portion 22 is with poor (R-r) and in radial direction closer to transition portion 210 Excircle, or in other words, teeth portion 22 in the case where in the first embodiment according to Figure 14 compared with less moulded deeply Into the cross section with tooth section 611.

Third embodiment according to the present invention with tooth section 612 is in Figure 22 with corresponding with the side view of Figure 14 Side view illustrates, and is shown in Figure 23 in the mode similar with the sectional view of Figure 18 with the section D-D for passing through toothed portion point 21 Out.As the embodiment of the last description with tooth section 611, rear portion axis Q is equally correspondingly inclined relative to longitudinal axis L It moves, specifically offset by interval or offset c2.Offset c2 in this embodiment greatly than semidiameter (R-r) so that transition The cross section of part 210 protrudes past back 23, as being observed that in the sectional view of Figure 23.Offset c2 is shown in Teeth portion 22 is chosen in example to terminate with flushing in height direction H with the circumference of transition portion 210.With band tooth section The case where 611 second embodiment, is compared, and teeth portion 22 is located at higher position relative to longitudinal axis L.

Due to method according to the invention it is possible to come in a simple manner as desired by the corresponding design of mold 5 real Existing offset c1 or c2.In detail, this can be accomplished in the following manner: be set according to semidiameter (R-r) to longitudinal axis L 53 holding meanss 55 and 56 being fixed of position, toothed die component points 51 and back mold component point between it is radial partially It moves, toothed die component 51 and back mold component 53 are by back 23 being formed the position to determine back axis Q.With The depth of this mode, teeth portion 22 can be according to the corresponding requirements in transfer 105 by means of the mould with relatively easy structure Have 5 to realize.

Another advantage according to the method for the present invention also resides in, rack gear particularly can also by less material input come It realizes, because semidiameter not will lead to any waste.Material input as a result, can be reduced, or even in blank by solid material shape It also can be such in the case where.

The rack gear of transfer for motor vehicles preferably realizes that the rack gear has along longitudinal axis in this way The toothed portion point 21 that line L extends, and be provided on the contrary about longitudinal axis L and toothed portion point 21 with back radius R's The back 23 of fan shape, wherein be configured with other cylindricality transition portion 201,211 in toothed portion points 21, it is described in addition Cylindricality transition portion 201,211 radius r be less than back radius R.Model of the semidiameter relative to back radius R 3% to 7% It is preferred in enclosing.Semidiameter is particularly preferably in the range of 4.5% to 6.5%.It can realize and well to shape at the same time In the case of realize that advantageous material is saved.

Another significant advantage is additionally provided according to the method for the present invention.In order to have toothed portion shown in example point Rack gear insertion transfer in, it is necessary to depend on multiple parameters.For example, the specific diameter of rack gear answer it is as small as possible, to save Save installation space.Particularly keep the flash width G B for being limited in two side structures of teeth portion width.After it is expected limit mechanical herein Processing.Particularly, the method by being proposed, described two flashes 29 may be implemented as with less than teeth portion width b's 25% corresponding flash width G B, without carrying out any mechanical post-treatments.Less than 18% corresponding hair of teeth portion width Hem width degree is preferred.Can by the parameter of optimization tool realize less than teeth portion width b 10% or particularly preferably at most For the 5% corresponding flash width G B of teeth portion width b.It therefore, there is no need to remove the flash 29 in the formation of the two sides of teeth portion, by This can reduce the mechanical post-treatments to toothed portion point 21.

After forging, band tooth section 61 (or corresponding 611 or 612) can be hardened in a continuous process, in Figure 24 Shown in.It is mobile by continuous heating 41 and by processing side that band tooth section 61 is parallel to longitudinal axis L herein It is located at the continuous cooling device 42 in 41 downstream of continuous heating on D.Can by accordingly select thermal parameter and when Between parameter make hardening of steel, as being had been described in principle above in conjunction with Fig. 3 for axis section semi-finished product 31.Thus, it is possible to Optimal hardness is set for stress expected in operation.

Figure 32 shows the band tooth section 63 at the back 231 with V-arrangement shape, and the back 231 of V-arrangement shape is called V for short Shape back 231.V-arrangement shape is formed by two V-arrangement supporting leg faces 232, when from teeth portion 22, the two V-arrangement supporting leg faces 232 with One angle is converged towards back 231.

The cross section at V-arrangement back 231 is fenced by the envelope circle with back radius R1, can such as obtain from the sectional view of Figure 35 Out.V-arrangement supporting leg face 232 includes the secant of envelope circle, and envelope circle is drawn in Figure 35 with dotted line.

The case where D-shape embodiment described in Figure 10 to Figure 24 above in conjunction, is the same, and transition portion 210 is adjacent Teeth portion 22.There is transition portion 210 radius r1, radius r1 to correspond to the not machined radius r1 of the blank 3 according to Figure 34.

Forging can carry out in mold 50 in the method in accordance with the invention, such as schemed in the mode similar with the section of Figure 16 Shown in section in 34, and as in the mode similar with the section of Figure 18 or Figure 23 shown in Figure 35.Mold 50 Toothed die component 51 be configured to the D-shape embodiment of above-mentioned mold 5.Unlike mold 5, back mold component 531 have cross section for the back moldable gap 541 of V-arrangement shape.

As can be drawn from Figure 34 how by the insertion back mold component 531 of blank 3 with not machined r1 and with tooth Between mold component 51.The envelope circle of back moldable gap 541 with back radius R1 is drawn with dotted line.It can be observed that It is that there is the blank of the lesser not machined radius r1 compared with back radius R1 under unfashioned not machined state 3 do not fill up mold 5 on width direction B, and blank 3 is not located in coaxial fashion in envelope circle.

Figure 35 shows the band tooth section 63 of the completion forged from blank 3.In the illustrative embodiments, back 231 by its envelope is round and transition portion 210 be arranged to it is coaxial with longitudinal axis L, that is, radius r1 and R1 and longitudinal axis L phase It closes, this is as the back of the D-shape in the illustrative embodiments according to Figure 10 to Figure 19 23.However, it is also possible to imagine And it is possible that being limited as the embodiment of according to fig. 20, Figure 21 or Figure 22, Figure 23 according to the requirement of transfer Surely it is used for the offset at V-arrangement back 231.

Figure 31 and Figure 32 shows the embodiment party of the rack gear 2 of toothed portion point 21 and shaft portion 24 with different-diameter condition Formula, wherein biggish diameter is had according to the shaft portion 24 of Figure 31.

It is according to the present invention for produce forging method with tooth section 61,611,612 or 63 the advantages of be, and such as show There is the case where not machined radius in technology corresponds to back radius to compare, being used to form has and back radius R (or phase The R1 answered) it is lower compared to forging force needed for the blank 3 of lesser not machined radius r (or corresponding r1).

With with such as above under the background at D-shape back discussed content same way at flash width and back half The same advantage obtained in terms of the Ratio Conditions of diameter R1 and not machined radius r1.

The rack gear of transfer for motor vehicles preferably realizes that the rack gear has axis along longitudinal direction in this way The toothed portion point 21 that line L extends, and the rack gear is provided on the contrary about longitudinal axis L and toothed portion point 21 with back The back 23 of the fan shape of radius R1, wherein be configured with another cylindricality transition portion 201,211, institute in toothed portion point 21 The radius r1 for stating another cylindricality transition portion 201,211 is less than back radius R1.Semidiameter is preferably the 3% of back radius R1 To in the range of 7%.Semidiameter is particularly preferably in the range of 4.5% to 6.5%.

The 25% corresponding flash less than teeth portion width b also can be implemented in the embodiment with V-arrangement back Width G B, without carrying out any mechanical post-treatments.Therefore, be preferably herein, realize be less than teeth portion width 20% or more Preferably less than the 15% of teeth portion width b or be particularly preferably at most teeth portion width b 10% corresponding flash width.

The method according to the present invention for producing rack gear 2 is shown into Figure 27 in Figure 25, wherein herein as threaded The axis section of section 35 is bonded to band tooth section 61 by means of friction welding.

Threaded section 35 can be for example as above in conjunction with being made described in Fig. 5 and Fig. 6.Threaded section 35 exists There is joint surface 28 with section length ls on the direction of longitudinal axis L and at the portion of an end side.

Band tooth section 61 can be for example by obtaining by means of method described in Figure 10 to Figure 23 or Figure 36 to Figure 40.Band Tooth section 61 has joint surface 28 with section length lz and equally at the portion of an end side.

Threaded section 35 is clamped in clamping device 70 and is aligned in coaxial fashion in longitudinal axis L, such as schemes Shown in 26.Clamping device 70 has clamping element 701,702 and 703 and pairing bearing 74.Clamping element 701,702 and 703 from external support between the screw thread item of screw thread 25 so that guarantee in longitudinal axis L limit alignment.Screw thread 25 is at this The plane of reference is formed in text.Threaded section 35 is in axial direction supported on pairing bearing 704 by its free end 26, thus Realize the accurate axially position on the direction of longitudinal axis L.

Band tooth section 61 is clamped in clamping device 71 and is aligned in longitudinal axis L with coaxial manner.Clamping device 71 have clamping element 711,712 and 713.Clamping element 711 and 712 is supported in teeth portion 22；Clamping element 713 is supported on back In portion 23.The functional surfaces of teeth portion 22 or the functional surfaces at back 23 are respectively formed at the reference precisely aligned in longitudinal axis L as a result, Face.

It is supported on the joint surface 28 of threaded section 35 with tooth section 61 by its joint surface 28.Band tooth section 61 passes through Its free end 26 is in axial direction supported on compression piece 714, and compression piece 714 is rigidly connected to by connecting element 715 The clamping element 711,712 and 713 of clamping device 71, and compressing member 714 relative to longitudinal axis L with not relative rotation Mode is connected.

Clamping device 71 can be driven by driving device (not shown) to be rotated at around longitudinal axis L, as by curved arrow institute It indicates.Contact pressure F on the direction of longitudinal axis L can be applied in by means of contact pressure arrangement (being equally not shown) On clamping device 71, as indicated by power arrow, and the clamped joint surface 28 with tooth section 61 passes through the contact Pressure F can be pressed against the threaded section 35 being clamped in clamping device 70 with axial manner and connect in the direction of axis L along longitudinal direction Conjunction face 28.Joint surface 28 carries out CONTACT WITH FRICTION each other as a result,.

Clamping device 71 after being clamped relative to clamping device 70 is located so that threaded section 35 and with tooth Section 61 is mutually supported by its joint surface 28, and threaded section 35 is axial to be supported on pairing bearing 704, and with tooth section 61 are supported on compression piece 714.Therefore, total spacing between compression piece 714 and pairing bearing 704, i.e. so-called initial gap L1 is equal to the summation of section length ls and lz, and therefore: (the length ls+ of threaded section 35 is with the length of tooth section 61 by L1=ls+lz Spend lz).

According to the present invention, clamping device 71 is arranged to rotation to carry out friction welding, so that joint surface 28 is in rubbing action Under rotate relative to each other.Herein, the frictional heat of release depends on rotation speed and contact pressure F.

Apply the contact pressure F for being in initial frictional F1 level, first to execute initial friction, the initial friction Power may be between such as 10kN and 30kN.Thus lead to the homogenization on the surface on joint surface 28.Initial friction can be lacked In 3 seconds duration.

Contact pressure F then increases to input power F2, and to carry out heat input friction, the input power F2 may be initial About 5 times to 12 times, preferably 6 times to 11 times of frictional force F1.Heat input friction is carried out to reach until at joint surface 28 For welding the desired processing temperature of steel.Fixed duration, or the temperature by measuring can be predefined herein Degree carrys out regulating time.The duration less than 15 seconds is preferably followed herein.

When reaching treatment temperature, contact pressure F increases to 10 times to 20 times of initial frictional F1, preferably increases to 17 times of initial frictional F1.It is compressed due to the material molten between the joint surface 28 at joint portion 27, wherein in institute It states in compression, band tooth section 61 and threaded section 35 are moved at joint portion 27 toward each other while forming the compression It is dynamic, shorten so that starting length L1.Controlling of path thereof according to the present invention only allows limited shortening, predetermined until reaching Target length L2.So-called blend path X is shortened, blend path X, which corresponds to, to be started between length L1 and target length L2 Difference: X=L1-L2.

The end-state for reaching overall length L2 is shown in FIG. 27.Target length L2 for example corresponding to such as Fig. 2 or The rack gear length Z of rack gear 2 shown in Figure 41, wherein shaft portion 24 has shaft portion length S, and shaft portion length S is due to welding And shorten relative to section length ls, and there is toothed portion point 21 toothed portion shorter than section length lz to divide length V.

When soldered, material is squeezed out in a radial manner at joint portion 27, and the material forms circular weldering pearl 271.

Schematically showing in Figure 28 can be generated at joint portion 27 by friction welding according to the present invention Hardness distribution.Heat input relevant to steel construction is changed is carried out due to friction welding, the heat input is in the side of longitudinal axis L It is correspondingly input in the heat-affected zone 91 of shaft portion 24 and the heat-affected zone 92 of toothed portion point 21 upwards.According to this hair Bright, welding parameter such as rotation speed and contact pressure F are preferably defined so that heat affected area 91 and 92 is heated at most 250℃.In case of the method according to the invention, heat affected area 91 and 92 preferably has the maximum width of 0.25 × ds, Wherein, ds correspondingly indicates the diameter of section 21 or the diameter of section 24.

It is most strong close to the heating in the radially outward circumferential area at joint portion 27.In the peripheral edge margin 93 of the coaxial surrounding Allow to increase to more 200HV1 relative to basic material hardness.The core area 94 being centered about in peripheral edge margin 93 is permitted Perhaps hardness increases to more 250HV1.Since the hardness increase in peripheral edge margin 93 increases lower than the hardness in core area 94, because And it avoids the formation of metallurgical recess and realizes bigger bearing capacity.

Rack gear for motor vehicles steering mechanism realizes that the rack gear is by the area Liang Ge advantageous by method management Section --- such as with tooth section 61 or with tooth section 63 and axis section 62 --- is formed, with tooth section 61 or with tooth section 63 and axis Section 62 is connected to each other by means of friction welding, wherein measuring and being greater than from the center of weld seam in longitudinal axis L The segment diameters ds of section with small diameter is multiplied by the maximum microhardness in 0.3 the first spacing, than in longitudinal axis On the microhardness 200HV1 most greatly at 1.5 times of the spacing of the segment diameters ds for the section with small diameter. The increase of hardness is preferably less than 120HV1.

Herein it is particularly preferred that measuring and being greater than the segment diameters of the section with small diameter from Weld pipe mill Ds is multiplied by the maximum microhardness in the surface in 0.3 spacing, than 1.5 times in the segment diameters ds for respective section The 250HV1 most greatly of the microhardness in surface at spacing.The increase of hardness is preferably less than 180HV1.

Figure 29 shows band tooth section 61 with solid.The band tooth section 61 has setting element 220, the positioning member Part 220 is disposed relative to the functional surfaces on the functional surfaces of teeth portion 22, the functional surfaces at back 23, joint surface 28 etc. in positions and dimensions Aspect is accurate.Setting element 220 can shape jointly in a simple manner in forging band tooth section 61.In addition, positioning Element 220, which such as can be ground, be etched by suitable machine-tooled method etc., is configured to the accurate plane of reference, and setting element 220 can be optimised for clamping device in terms of shape and arrangement --- the clamping element for example engaged in form-fit fashion Such as the clamping element 701,702,703,711,712 or 713 of 6 and Figure 27 according to fig. 2 --- in the clamping face for clamping.

Figure 30 shows the embodiment of the rack gear 20 of construction, and the rack gear 20 of construction has toothed portion point 21 and as axle portion Divide the second toothed portion point 213 for being connected to the toothed portion point 21.Toothed portion point 21 and toothed portion point 213 are by means of friction welding It is connected at joint portion 27.Toothed portion divides 21 and both toothed portion point 213 has teeth portion, and the teeth portion is added by mechanical Work is for example combined by milling.It is likewise contemplated that and it is possible that the teeth portion with milling toothed portion point by means of Friction welding is connected to the toothed portion point of forging.

Figure 36 and Figure 37 shows the rack gear made according to the present invention in another embodiment.Rack gear 2 has toothed portion Divide 21, toothed portion point 21 is provided with the teeth portion 22 that A extends along the longitudinal direction on a side.Rack gear 2 also has shaft portion 24, Shaft portion 24 has screw thread 25 in the example shown in Figure 41, and shaft portion 24 is also referred to as threaded section 24.Band tooth Part 21 has transitional region 210, and transitional region 210 includes reduced diameter portion point at the free end of transitional region 210 217.The diameter D5 of reduced diameter portion point 214 is smaller than the diameter D2 of transition portion 210.Shaft portion 22 has transitional region 215, mistake Crossing region 215 includes reduced diameter portion point 216 at the free end of transition portion 215.The diameter D4 of reduced diameter portion point 216 It is smaller than the diameter D1 of transition portion 216.Toothed portion point 21 and shaft portion 22 divide 21 reduced diameter portion point 217 and axis in toothed portion These ends of the facing each other in the axial direction of the reduced diameter portion of part 22 point 216 are connect by means of toothed portion point 21 Conjunction face 28 and the joint surface of shaft portion 22 28 and be connected to each other by frictionally engaging in joint portion 27.In welding, material It is squeezed out in a radial fashion at joint portion 27, the material forms the circular weldering pearl 271 with envelope circular diameter D3.Weld pearl The 271 envelope circular diameter D3 is less than the diameter D1 of reduced diameter portion point 216 and is less than the diameter of reduced diameter portion point 214 D2.Envelope circular diameter D3 is greater than the diameter D4 of reduced diameter portion point 216 and is greater than the diameter D5 of reduced diameter portion point.Due to envelope Circular diameter D3 is less than diameter D1, D2, because carrying out mechanical post-treatments without butt welding pearl 217, because weldering pearl 271 is with radially outward Mode it is prominent without transition portion 210,215 it is far prominent in a manner of radially outer.

The alternative embodiment of the rack gear 2 similar with the rack gear of Figure 41 and 42 is shown in the detailed view of Figure 38. Envelope circular diameter D3 is configured to be greater than the diameter D5 of the reduced diameter portion point 217 and diameter D2 of transition portion 210.According to the present invention Envelope circular diameter D3 be less than shaft portion 24 transitional region 215 diameter D1.The transitional region 215 of shaft portion 24 has screw thread 25, in this embodiment, screw thread 25 extends in the whole length of shaft portion 24.Therefore, transition portion indicates shaft portion The part adjacent with joint portion 27.Since the envelope circular diameter D3 of weldering pearl 271 is less than the diameter D1 of transitional region 215, thus can To be accomplished that, weld pearl 271 it is prominent not in a manner of radially outward being interfered and do not need butt welding pearl 2 carry out it is any additional Subtract material machining there is no transitional region 215 with diameter because weldering pearl 271 according to the present invention is prominent in a manner of radially outer It is far prominent to outside mode.

Claims (13)

1. a kind of for producing the method for being used for the rack gear (2) of transfer of motor vehicles, the rack gear (2) includes having tooth At least one toothed portion in portion (22) point (21) and at least one shaft portion (24) at least one threaded section, it is described At least one threaded section has coaxial screw thread (25), and the screw thread (25) has spiral shell on the direction of longitudinal axis (L) Line length,

Wherein, separated section is provided, the separated section includes at least one bacillary band tooth section in each case (61) it is aligned on shared longitudinal axis (L) with an axis section (62), the separated section and at joint portion (27) it is connected to each other,

It is characterized in that following step:

The axis stock piece (36) with part length (G) is provided, the part length (G) is the multiple of axis section length (ls)；

In generating continuous spiral shell in a longitudinal direction on the multiple length of the reach on the axis stock piece (36) Line, to produce threaded semi-finished product (37)；

Threaded section (62) are cut into from the threaded semi-finished product (37) by length；

Band tooth section (61) is provided；

The threaded section (62) is bonded to the band tooth section (61).

2. the method according to claim 1, wherein the screw thread (25) on the axis stock piece (36) with Continuous axial direction processing method generates.

3. according to the method described in claim 2, it is characterized in that, the screw thread (25) rotation is process.

4. method according to one of the preceding claims, which is characterized in that the screw thread (25) has ball-screw At least one ball road of transmission device (KGT).

5. method according to one of the preceding claims, which is characterized in that the shaft portion stock piece (36) mentions For for heat-formable material part and/or cold forming material part and/or subtracting material machining materials part.

6. method according to one of the preceding claims, which is characterized in that the shaft portion stock piece (36) mentions For for bar or pipe, be preferably provided as rounded material.

7. method according to one of the preceding claims, which is characterized in that right before in conjunction with the screw thread (25) The shaft portion stock piece (36) is heat-treated.

8. method according to one of the preceding claims, which is characterized in that by providing the axis by length cutting At least one end side end surface of section (62), to construct joint surface (28).

9. method according to one of the preceding claims, which is characterized in that the band tooth section (61) and the axis Section (62) is soldered to each other.

10. method according to one of the preceding claims, which is characterized in that funtion part includes another section of rack (213) and/or threaded section (24) and/or coupling part.

11. method according to one of the preceding claims, which is characterized in that provide at least one other functional areas At least one described other function section is simultaneously bonded to the band tooth section (61) and/or the axis section (62) by section.

12. a kind of rack gear (2) of transfer for motor vehicles, the rack gear includes at least one with teeth portion (22) Toothed portion point (21) and at least one shaft portion (24) with screw thread (25), which is characterized in that the screw thread is in entire axle portion Extend on point length S.

13. rack gear according to claim 12, which is characterized in that the pitch of the continuous screw thread 5mm and 40mm it Between.